Guernsey Rugby Club boss Jordan Reynolds says he is disappointed with his side's 28-24 loss at Old Elthamians in London One South.
The loss sees Guernsey drop from second to fourth in the table.
"It was disappointing, we had an opportunity to win the game and gain a bonus point victory, but we made a bad decision," Reynolds told BBC Guernsey.
"That's costly in these games and we can't afford to do that against any other side."
He added: "Hopefully it'll be a learning curve for our younger players, if it's not then there's not much you can take out of that game, but hopefully we can learn from that and move on."